The Moodz detector lives !

[Old cart]

I ordered and have read threw the book now, and in some areas several times. Some of the stuff I think I understand some of and some of it I will just have to play with to see how it works. One thing I think the book was missing is maybe a short section on the care and feeding of the oscilloscope. I have never used one but ordered one from flea central and it arrived today. Now all I have to do is figure out how to use the thing. Any one know a good site that has a primer for idiots?

Picked up an HP 100mhz 2 channel. Probably like using a large pizza paddle to kill a fly, but it was in good shape and had a 90 day warranty.

That should be a good scope. You should start by reading this

https://courses.physics.illinois.edu/phys406/Lab_Handouts/XYZs_of_Oscilloscopes.pdf

this is the English version of a basic oscilloscope booklet. It was written by Tektronix, a leader in the field and is well done. If you want it in another language you can go to Tektronix.com and find the downloads. You wil have to create an account but they will not bother you.

Once you have read this connect the scope to it's calibrator via a probe. Using the calibrator or other known signal just play with the scope using what you have learned. You wil learn quickly this way.
if you have questions about probes, and many people do you can download ABCs of probes from the same site.
Both of these are good docs for beginners.
There are other docs there as well, they are all free.

enjoy!

[DanWho]

I ordered and have read threw the book now, and in some areas several times. Some of the stuff I think I understand some of and some of it I will just have to play with to see how it works. One thing I think the book was missing is maybe a short section on the care and feeding of the oscilloscope. I have never used one but ordered one from flea central and it arrived today. Now all I have to do is figure out how to use the thing. Any one know a good site that has a primer for idiots?

Picked up an HP 100mhz 2 channel. Probably like using a large pizza paddle to kill a fly, but it was in good shape and had a 90 day warranty.

[raygdunn]

I wish I knew more about metal detecting electronics, my experience lies more with ham radio, but it has been many years since I did much in that direction too. I need to find a good primer on the basics of the circuitry.

Any suggestions on where to start?

Hi Dan,

I can heartily recommend "Inside the Metal Detector". I started by reading it a year ago. Both the authors are here on the forum. Qiaozhi is one of them. If you are happy with the workings of very basic circuits, this will take you on from there. There are plenty of circuits one can breadboard and experiment with. I put one (PI-1) on Veroboard and it's been a very effective detector. The book will provide a good background, if you are thinking of trying one of the kitted projects associated with the forum (http://www.silverdog.co.uk).

Ray

[Qiaozhi]

I wish I knew more about metal detecting electronics, my experience lies more with ham radio, but it has been many years since I did much in that direction too. I need to find a good primer on the basics of the circuitry.

Any suggestions on where to start?

Inside the METAL DETECTOR - Second Edition - Published 2015

ISBN 978-0-9858342-1-0

[DanWho]

I wish I knew more about metal detecting electronics, my experience lies more with ham radio, but it has been many years since I did much in that direction too. I need to find a good primer on the basics of the circuitry.

Any suggestions on where to start?

[moodz]

Hey Billy, Your Also Welcome, Another Nice, Kind, Encouraging Response.

[BILLY]

No .. not at all ... I was not satisfied with the ground balance system and as a secondary consideration the TX pulse efficiency. A novel ground cancellation system is being tested and the TX efficiency is also working ( its about 90% efficient in air ... drops about 5% in mineralised ground ). Once the testing is done I will roll out another board layout.

That is great news Moodz! So you should have a good machine by the years end, right? Even better than any machine on the market. How are the coils coming along?

[moodz]

Did this project die out due to difficulties of making surface mount boards and parts, or just trying to source non-surface mount parts? Any progress in any direction?

No .. not at all ... I was not satisfied with the ground balance system and as a secondary consideration the TX pulse efficiency. A novel ground cancellation system is being tested and the TX efficiency is also working ( its about 90% efficient in air ... drops about 5% in mineralised ground ). Once the testing is done I will roll out another board layout.

[DanWho]

Did this project die out due to difficulties of making surface mount boards and parts, or just trying to source non-surface mount parts? Any progress in any direction?

[soverey]

As soon as a pcb file and list of materials is ready , I would like to give it a try.

[Old cart]

I have been experimenting with an auto ground cancellation system ... but that is another story ... I have the "backend" completed ( this is all the power supplies, sampling, control, drivers etc ) .... see below.

I just need to put an edge connector or something so that different front ends can be plugged on.

See below ... This is the current board ... I have just snipped the front end off so you can see what the back end will look like.

The board size is 8cm x 8cm ... all the parts are surface mount except for the micro so it can be replugged / upgraded etc.



[ATTACH]34024[/ATTACH]

Board looks good. Is it possible to get a little more contrast and/ or less overlap between the part nomenclatures? It is a bit hard to read. I like the use of multiple caps in parallel to lower ESR/ESL. Would there be any befenefit of adding a film cap in parallel with each bank to lower the high frequency impedance, or is this not necessary?

[soverey]

I have been experimenting with an auto ground cancellation system ... but that is another story ... I have the "backend" completed ( this is all the power supplies, sampling, control, drivers etc ) .... see below.

I just need to put an edge connector or something so that different front ends can be plugged on.

See below ... This is the current board ... I have just snipped the front end off so you can see what the back end will look like.

The board size is 8cm x 8cm ... all the parts are surface mount except for the micro so it can be replugged / upgraded etc.



[ATTACH]34024[/ATTACH]

Thank you for the update , board looks pretty compact, sorry I can't offer more technical comments, advice. Looking forward to see how the projects evolves.

[moodz]

Hey guys ,
I wanted to know whether using two or three power Mosfets in series is a right thing to do,
I simulated this topology and I want to use two C2M0280120D Power mosfets.it's 1200v Vds and !0A Id and 22mOhm Rds(on) with 24ns Reverse Recovery time and falling time of 21ns.

I want to switch from a 48v li-ion battery separately.
what's your opinion guys? could you help me in the driver design?
you all seem to have many experience in PI.
I want to design a humanitarian de-mining device.

DONT OPEN THIS LINK ...its bogus ( maybe this user needs to be edumacated :-) )

[moodz]

Any progress on the building document?

I have been experimenting with an auto ground cancellation system ... but that is another story ... I have the "backend" completed ( this is all the power supplies, sampling, control, drivers etc ) .... see below.

I just need to put an edge connector or something so that different front ends can be plugged on.

See below ... This is the current board ... I have just snipped the front end off so you can see what the back end will look like.

The board size is 8cm x 8cm ... all the parts are surface mount except for the micro so it can be replugged / upgraded etc.

[moodz]

Why i can't open the Moods pulsar on australian,i am interesting by your detector,regards.

Hi ... the pulsar detector was only a "mind experiment" ... it is not this thread. It should be visible on the other site ... ( not sure if I am allowed to link to it :-| )